1. Field of the Invention
The present invention relates to ion-removing apparatus for removing ions contained in a fluid.
2. Description of the Related Art
Various types of ion-removing apparatus are known. For example, Japanese Laid-Open Patent Publication No. 2002-313404 teaches an ion-removing apparatus 50 shown in FIG. 4. The ion-removing apparatus 50 is designed for removing ions contained in a fluid that is discharged from a fuel cell 51. The ion-removing apparatus 50 includes a container 52 and an ion exchange resin 54. The container 52 stores water. The ion exchange resin 54 is disposed within the container 52 and is immersed into the water. The fluid that has been discharged from the fuel cell 51 may flow through the water within the container 52, so that the liquid contained in the discharged fluid may be left to be contained in the water, while the gas contained in the fluid may be discharged as bubbles from the container 52. The liquid remained in the water may contain ions. The ion exchange resin 54 may adsorb the ions, so that the ions may be removed from the fluid that has been discharged from the fuel cell 51.
However, it is difficult to efficiently remove a number of different kinds of ions, such as anions and cations, contained in the fluid by the use of the above ion-removing apparatus 50. For example, assuming that the ion exchange resin 54 includes an ion exchange resin for removing anions (hereinafter called “resin A”) and an ion exchange resin for removing cations (hereinafter called “resin B”) and that the resin A and resin B are disposed separately from each other, it is difficult to adsorb cations positioned proximally to the resin A (for anions) by the resin B (for cations). Similarly, it is difficult to adsorb anions positioned proximally to the resin B by the resin A. Therefore, the efficiency in general for removing anions and cations is degraded.
This may be improved by positioning the resins A and the resins B such that they are uniformly mixed with each other. However, if the resins A have become unusable while the resins B still can be used, it is necessary to change both the resins A and B to new ones.